Proteomic Study of Hypothalamus in Pigs Exposed to Heat Stress

Background: With evidence of warming climates, it is important to understand the effects of heat stress in farm animals in order to minimize production losses. Study of changes in the brain proteome induced by heat stress may aid in understanding how heat stress impacts brain function. The hypothalamus is a key region in the brain that controls the pituitary gland, which is responsible for the secretion of several important hormones. Result: In this study, we examined the hypothalamic protein profile of ten pigs (30–40 kg body weight), 5 of which were subjected to heat stress (35 ± 1°C; relative humidity = 90%) and 5 acting as controls (28 ± 3°C; RH = 90%). The isobaric tags for relative and absolute quantification (iTRAQ) analysis of the hypothalamus identified 1710 peptides corresponding to 360 proteins, and 295 deferentially expressed proteins (DEPs), 148 of which were up-regulated and 147 down-regulated in heat-stressed animals. Ingenuity Pathway Analysis software predicted 30 canonical pathways, 4 functional groups, and 4 regulatory networks of interest and the DEPs mainly concentrated in the cytoskeleton of the pig hypothalamus during heat stress. Conclusions: The upstream regulators of these 295 DEPs in the hypothalamus of the pig under HS are mainly transcriptional regulators, chemical drugs, and sRNA. This study provides reference data for further study of the mechanism of HS on hypothalamic physiology and metabolism(Illustration 1).